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The present article has utilized the WIEN2k computational code to examine the structural, elastic, electronic, magnetic, thermoelectric, and dynamic aspects of the CoCrS Half-Heusler (HH) compound. In this work, calculations have been performed by utilizing the full-potential linearized augmented plane wave method using density functional theory. The electronic bandgap was better interpreted by using the modified Becke–Johnson exchange–correlation functional. We evaluated various electronic properties of the CoCrS HH compound, including band structure plots and density of states. Furthermore, we examined the magnetic characteristics through the computation of magnetic moments and the examination of the spin-polarized electronic state behavior. We also determined the elastic properties of the CoCrS HH compound. These properties, which include stiffness, resilience, and general stability, provide important information about how the material responds to mechanical deformation. Moreover, we explored the electronic structure and found that type 5 of CoCrS exhibits a metallic behavior. In addition, we examined the compound's thermoelectric properties. Finally, the dynamical properties indicate that type 5 of CoCrS is dynamically stable. [ABSTRACT FROM AUTHOR]

Both electronic as well as magnetic characteristics of Co1-xFexMnSb (x = 0, 0.25, 0.50, 0.75, 1) composite have been studied by employing the first principle (FP) study. The FP calculation was attained using the density functional theory (DFT). The exchange–correlation term has been examined inside the generalized gradient approximation (GGA), as implemented in the Wien2k code. According to predictions, the type 3 structure of atoms will be the tremendous, optimum, and have the smallest amount of energy. The formation energy of CoMnSb and FeMnSb was minimum so it demonstrates that these alloys are optimized. CoMnSb and FeMnSb are half-metallic (HM) having the value of magnetic moment 3µB and 2µB, respectively in good agreement with the Slater-Pauling rule. These results suggest that the Mn atoms are the primary source of the magnetic moment. The values of elastic constants were determined by the crystal structure's symmetry. Additionally, the bulk modulus B, shear modulus G, Young's modulus E, as well as Poisson's ratio v have been determined using the Voigt-Reuss-Hill (VRH) method. Both examined compounds, CoMnSb and FeMnSb, have computed B/G ratios higher as compared to 1.75, indicating that these alloys are malleable. [ABSTRACT FROM AUTHOR]

The structural, mechanical, and electronic properties of rubidium iodide (RbI) have been extensively investigated utilizing the generalized gradient approximation (GGA) and the full-potential linearized augmented plane wave (FP-LAPW) approach. The potential was roughly calculated using a modified Becke–Johnson (mBJ) approximation, which increased the precision of the electronic properties. In this study, RbI is analyzed in a wide range of crystal structures, including topologies like rock salt (RS), CsCl, zinc blende (ZB), NiAs, and wurtzite (WZ), among others. Our research shows a strong relationship between the material's physical properties and the conclusions drawn from both theoretical and experimental studies. Significantly, our results show that the RS form corresponds to RbI's ground state. All the aforementioned topologies display wide-bandgap semiconductor capabilities, according to further examination of their electronic band structures. Notwithstanding these findings, it was discovered that RbI has a poor fracture resistance due to its low bulk modulus. Born's stability analysis has shown that RbI is stable in the RS, CsCl, ZB, NiAs, and WZ structures. All RbI structures were discovered to have ionic bonding and to be ductile, and every stabilized system displayed anisotropic stability. Using the Cauchy pressure and Poisson's ratio, the stiffness of the systems was evaluated, with the RS structure proving to be the stiffest. Overall, the findings illuminate the physical properties of RbI, providing valuable insights that could facilitate the creation and refinement of novel materials possessing desirable characteristics. [ABSTRACT FROM AUTHOR]

In this article, the structural, elastic, electronic, and magnetic characteristics of both regular and inverse Heusler alloys, Sc2TiAl and Sc2TiSi, were investigated using a full-potential, linearized augmented plane-wave (FP-LAPW) method, within the density functional theory. The optimized structural parameters were determined from the minimization of the total energy versus the volume of the unit cell. The band structure and DOS calculations were performed within the generalized gradient approximation (GGA) and modified Becke–Johnson approaches (mBJ-GGA), employed in the Wien2K code. The density of states (DOS) and band structure (BS) indicate the metallic nature of the regular structure of the two compounds. The total spin magnetic moments for the two compounds were consistent with the previous theoretical results. We calculated the elastic properties: bulk moduli, B , Poisson's ratio, ν , shear modulus, S, Young's modulus (Y), and the B/s ratio. Additionally, we used Blackman's diagram and Every's diagram to compare the elastic properties of the studied compounds, whereas Pugh's and Poisson's ratios were used in the analysis of the relationship between interatomic bonding type and physical properties. Mechanically, we found that the regular and inverse full-Heusler compounds Sc2TiAl and Sc2TiSi were stable. The results agree with previous studies, providing a road map for possible uses in electronic devices. [ABSTRACT FROM AUTHOR]

The structural, elastic, electronic, magnetic, and thermoelectric properties of MgEu2X4 (X = S and Se) spinel compounds are investigated computationally. Calculations are performed using the full‐potential linearized augmented plane wave (FP‐LAPW) method within the Perdew, Burke, and Ernzerhof generalized gradient approximation (PBE‐GGA), GGA + U, and modified Becke–Johnson (mBJ‐GGA) approximations. The band structure and density of states results from the three exchange‐correlation approximation methods (mBJ, GGA + U, and PBE) show that these spinel compounds are fully spin‐polarized. Also, they possess a half‐metallic character in the spin‐down channel with a direct bandgap (Γ–Γ) of about 3.44, 2.712, and 2.472 eV for MgEu2S4 and 2.89, 2.285, and 2.017 eV for MgEu2Se4, respectively. The formation of both compounds is energetically favorable based on the results of the total energy and cohesive energy calculations. Furthermore, the two compounds are chemically and mechanically stable, as concluded from cohesive energy and elastic calculations. The elastic calculations reveal that both spinel compounds are ductile materials. The ionic bonds are predominant. The quasi‐harmonic model has also been used to investigate the influences of temperature and pressure on thermal characteristics. The thermoelectric behavior is studied using the BoltzTraP code. Both systems show good thermoelectric properties for the spin‐down channel. [ABSTRACT FROM AUTHOR]

The magnetic, electronic and optical properties of alloys for selected concentrations ( x = 0, 0.25, 0.50, 0.75 and 1.0) were investigated by means of density functional theory (DFT) calculations utilizing full potential linearized augmented plane wave (FP-LAPW) method. It was found that doping the alloy with rare-earth ions like Eu generates the nonstoichiometric and changes its original behavior from half ferromagnetic material to a metallic one. In addition, the total magnetic moment was found to increase with increasing dopant concentration with maximum local magnetic contributions on the Eu-sites. The optical dielectric functions as well as their static value for all the above alloys were also investigated. Moreover, the absorption coefficient, reflectivity and refractive indices were calculated. All the optical calculations were found to agree well with the band structure calculations when determining the alloys' half-metallic behavior. Finally, the nonstoichiometric metallic compounds found in this series might be useful in the flat panel industry as potential phosphors. [ABSTRACT FROM AUTHOR]

This study investigates the influence of hydrostatic pressure on structural, electronic, mechanical and optical properties of Sr3PX3 (X = Cl and Br) compounds, by using the first-principles density functional theory (DFT) within the pressure range of 0–30 GPa with a span of 10 GPa. For Sr₃PCl₃ and Sr3PBr3, the dynamical stability is confirmed by the fact that the phonon dispersion curves do not contain imaginary modes. Pressure-induced band gap alterations in Sr3PCl3 and Sr3PBr3 reveal semiconducting behavior: GGA measurements show a decrease from 1.70 eV and 1.55 eV at ambient pressure to 0.22 eV and 0.21 eV at 30 GPa; TB-mBJ results show a decrease from 2.73 eV and 2.40 to 1.07 eV and 0.92 eV. This supports their inverse relationship with pressure. The values of Debye and melting temperatures support their high-temperature applications. Effective mass also shows an inverse relationship with induced pressure. The bond length, lattice parameters, and cell volume reduces with pressure. They exhibit ductility, which is further enhanced by the applied pressure. These materials emerge as promising candidates for flexible optoelectronic devices. Optical properties like absorption coefficients, reflectivity, and dielectric functions were observed and found to be significantly influenced by applied pressure. The absorption spectra exhibit a significant redshift with increasing pressure, indicating enhanced potential for optoelectronic applications. Our detailed investigation sheds light on the tunability of Sr3PX3 (X = Cl and Br) properties under pressure, showcasing their potential for cutting-edge applications in optoelectronics and photovoltaics. [ABSTRACT FROM AUTHOR]

The structural, mechanical, electronic and optical properties of SrTMO3 (TM = Rh, Zr) compounds are investigated by using first principle calculations based on density functional theory (DFT). The exchange-correlation potential was treated with the generalized gradient approximation (GGA) for the structural properties. Moreover, the modified Becke-Johnson (mBJ) approximation was also employed for the electronic properties. The calculated lattice constants are in good agreement with the available experimental and theoretical results. The elastic constants and their derived moduli reveal that SrRhO3 is ductile and SrZrO3 is brittle in nature. The band structure and the density of states calculations with mBJ-GGA predict a metallic nature for SrRhO3 and an insulating behavior for SrZrO3. The optical properties reveal that both SrRhO3 and SrZrO3 are suitable as wave reflectance compounds in the whole spectrum for SrRhO3 and in the far ultraviolet region (FUV) for SrZrO3. [ABSTRACT FROM AUTHOR]